As a U.S. diplomat pushed Cambodia's warring political parties to reopen talks, the country's top trial court added six-months to the pretrial detention of five people charged in connection with the government's case against opposition leader Kem Sokha. The Phnom Penh Municipal Court said it had extended the detention of the four employees of the human rights group ADHOC and the deputy secretary-general of the National Election Commission as it attempts to find more witnesses and evidence in the government's case agaisnt the opposition Cambodia National Rescue Party (CNRP) leader. An attorney for the accused decried the extra prison time, telling RFA's Khmer Service the additional detention violates their constitutional rights. "The legal proceedings are flawed," said attorney Sam Sokong. "The investigating judge should have exercised his due diligence efficiently during the six months while my clients had been under provisional detention to find additional witnesses and evidence against them." On May 2, Cambodian authorities arrested Cambodian Human Rights and Development Association (ADHOC) staffers Ny Sokha, Nay Vanda, Yi Soksan, and Lim Mony and National Election Committee (NEC) Deputy Secretary-General Ny Chakrya in a wide-ranging probe into a sex scandal involving Kem Sokha. "Drop all charges and release them' Sam Sokong urged investigating Judge Theam Chanpisith to release the defendants as no new evidence has come to light. "Now that the period has lapsed and no new evidence has been established, he ought to use his discretion to drop all charges and release them," he said. On Sept. 9 the Phnom Penh Municipal Court ruled that Kem Sokha was guilty of refusing to appear for questioning in the government's case against him, and he was sentenced to five months in prison and given a fine of 800,000 riel ($200). Kem Sokha is accused of procuring a prostitute in relation to his alleged affair with hairdresser Khom Chandaraty. Despite being summoned twice in May, he refused to appear in court to answer questions about the allegations and has remained holed up in CNRP headquarters. The ADHOC employees and Ny Chakrya are charged with bribery or being an accessory to bribery for allegedly attempting to pay Khom Chandaraty hush money. The charges are viewed by many as an attempt by Prime Minister Hun Sen and the ruling Cambodian People's Party (CPP) to smear the opposition before local elections in 2017 and national elections in 2018. Hun Sen and the CPP have ruled the country for more than three decades, but Cambodia's ruling party suffered a dramatic drop in support during the country's last election in 2013, and could see even more erosion in the upcoming elections. On Sept. 9 Kem Sokha was convicted failing to appear before the court in the case and sentenced to five months in prison and fined 800,000- riel (U.S. $200). A diplomat's appeal While the court was keeping the Kem Sokha five in jail, Daniel Russel, U.S. assistant secretary of state for East Asian and Pacific affairs, was appealing to party leaders to resume talks. Russel received assurances from both Kem Sokha and Foreign Minister Prak Sokhonn that the two sides could work things out. "Daniel Russel stated very clearly that there can be no free and fair elections if leaders of the opposition party and the opposition party in general cannot take part due to intimidation and restrictions," CNRP spokesman Yem Ponhearith told RFA. Prak Sokhonn meanwhile informed Russel of positive developments in the political situation, Foreign Ministry spokesman Chum Sounry told reporters after the meeting, according to the Associated Press. Addressing a group of reporters, Russel said the U.S. wants to play a conciliatory role in the escalating war of words between the two opposing political factions. "Rather than pass judgment, we are here to consult and put heads together with our Cambodian counterparts on how we can advance the goals of due process, rule of law and economic growth," he said, according to a report in the Khmer Times. UPDATE: On 13 March 2017, the Supreme Court upheld the Court of Appeal's decision to extend the pre-trial detention of senior ADHOC staff and human rights defenders, Lim Mony, Ny Sokha, Nay Vanda and Yi Soksan, subsequent to the initial passing of the six month detention mark at the end of 2016. The fifth human rights defender involved in the case, Ny Chakrya, will appear before the Supreme Court on 24 March 2017. UPDATE: On 27 April 2017, the Phnom Penh Municipal Court extended the pre-trial detention of senior ADHOC staff and human rights defenders, Lim Mony, Ny Sokha, Nay Vanda, Yi Soksan and Ny Chakrya by an additional six months, purportedly to further investigate their case. The five human rights defenders have already spent a year in pre-trial detention.